Wanted to find out an official ruling about how predator actually triggers.

Is it only when a hero voluntarily moves at least one square away so it isn't in base contact anymore with the character with predator, or does it also trigger if the hero moves to a square that is still adjacent to the model with predator but not in the square it started in?

Also, as the hero is not choosing to move voluntarily, do abilities like push, pull and compel also cause predator to trigger?

I am assuming abilities like teleport or place abilities do not trigger predator as they are not moving but appearing in a new location.

True, it also can be interpreted as meaning you need to leave adjacency to gain the hit though, a punishment for running away. That's what I am wondering about, if you only need to move side to side along a models base or fully away for it to trigger. Also if it is only from voluntarily moving away/compel or with push effects.

From the wording, you could compel the model back and forth and attack with predator after every move. Is the square it moved out of adjacent? Yes? Predator triggers. It's not tied to the square moved into.